Commitments and Contingencies - Additional Information (Detail)	1 Months Ended			1 Months Ended	3 Months Ended	12 Months Ended																												12 Months Ended
	Aug. 31, 2014	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Nov. 30, 2010 Cygnet Health Care Limited Facility Patient	Sep. 30, 2014 Cygnet Health Care Limited Facility	Dec. 31, 2014 Cygnet Health Care Limited GBP (£)	Nov. 30, 2010 Professional Liability Cygnet Health Care Limited GBP (£)	Nov. 30, 2010 General Liability Cygnet Health Care Limited GBP (£)	Dec. 31, 2014 Location 2 USD ($)	Dec. 31, 2014 Location 1 USD ($)	Dec. 31, 2014 Wind Storms Maximum USD ($)	Dec. 31, 2014 Wind Storms Minimum	Dec. 31, 2014 Earthquake USD ($)	Dec. 31, 2014 Earthquake Maximum USD ($)	Dec. 31, 2014 Earthquake UNITED STATES Maximum USD ($)	Dec. 31, 2014 Earthquake UNITED STATES Minimum	Dec. 31, 2014 Earthquake PUERTO RICO USD ($)	Dec. 31, 2014 Flood Location 2 USD ($)	Dec. 31, 2014 Flood Location 1 USD ($)	Nov. 30, 2010 Subsidiaries Professional Liability Maximum USD ($)	Nov. 30, 2010 Subsidiaries General Liability Maximum USD ($)	Dec. 31, 2014 Subsidiaries General and Professional Liability Insurance Policies	Dec. 31, 2014 Subsidiaries General and Professional Liability Insurance Policies Maximum USD ($)	Dec. 31, 2013 Subsidiaries General and Professional Liability Insurance Policies Maximum USD ($)	Dec. 31, 2014 Subsidiaries General and Professional Liability Insurance Policies Minimum USD ($)	Dec. 31, 2014 Psychiatric Solutions Inc General and Professional Liability Insurance Policies Maximum USD ($)	Oct. 31, 2012 Behavioral Health Facilities Acquired from Ascend Health Corporation General and Professional Liability Insurance Policies USD ($)	Dec. 31, 2014 Revenue Cycle Data Processing Services USD ($)	Dec. 31, 2014 Electronic Health Records Application USD ($)	Dec. 31, 2014 Estimated Minimum Liabilities For Physician Commitments USD ($)	Dec. 31, 2014 Construction Commitment USD ($)	Dec. 31, 2014 Related to Certain Equipment USD ($)	Dec. 31, 2014 Commercial Health Insurer and Self-insured Employee Benefit Plans USD ($)	Dec. 31, 2014 Professional And General Liability Psi Subsidiaries USD ($)	Dec. 31, 2013 Professional And General Liability Psi Subsidiaries USD ($)	Dec. 31, 2012 Professional And General Liability Psi Subsidiaries USD ($)	Dec. 31, 2011 Professional And General Liability Psi Subsidiaries
Commitments and Contingencies Disclosure [Line Items]
Self-insured for professional and general liability		$ 193,000,000	$ 206,000,000				£ 10,000,000	£ 25,000,000												$ 10,000,000	$ 3,000,000					$ 3,000,000	$ 12,000,000
Purchased several excess policies through commercial insurance carriers per occurrence																							250,000,000	200,000,000
Percentage of liability for claims paid under commercially insured coverage																						10.00%
Liability for claims paid under commercially insured coverage																							60,000,000		10,000,000
Minimum Insurance Deductible									250,000	50,000			250,000														100,000
Number of patients				16
Number of facilities				18	17
Number of nursing homes				2	2
Self-insured for professional and general liability, current		51,000,000	44,000,000
Reduction in professional and general liability self-insurance reserves relating to prior years																																		20,000,000	81,000,000	27,000,000
Weighting given to company-specific metrics																																				100.00%	75.00%
General industry metrics																																				0.00%	25.00%
Compensation liability claims		67,000,000	64,000,000
Compensation and related benefits		32,000,000	34,000,000
Commercial property insurance policies covering catastrophic losses											1,000,000,000			250,000,000	100,000,000		25,000,000
Percentage of insurance deductible											5.00%	3.00%			5.00%	1.00%
Maximum insurance deductible																	25,000	250,000	500,000
Property insurance						180,000,000
Payment suspension period increased	180 days
Combined estimated future purchase obligations		205,000,000																										87,000,000	117,000,000	2,000,000	151,000,000	251,000,000	58,000,000
Defined benefit pension plan estimated payments through 2089		234,000,000
Other retirement plan liabilities		$ 17,000,000